3,553 research outputs found
KM3NeT:a large underwater neutrino telescope in the Mediterranean Sea
High energy neutrinos produced in astrophysical processes will allow for a
new way of studying the universe. In order to detect the expected flux of high
energy neutrinos from specific astrophysical sources, neutrino telescopes of a
scale of a km^3 of water will be needed. A Northern Hemisphere detector is
being proposed to be sited in a deep area of the Mediterranean Sea. This
detector will provide complimentary sky coverage to the IceCube detector being
built at the South Pole. The three neutrino telescope projects in the
Mediterranean (ANTARES, NEMO and NESTOR) are partners in an effort to design,
and build such a km^3 size neutrino telescope, the KM3NeT. The EU is funding a
3-year Design Study; the status of the Design Study is presented and some
technical issues are discussed.Comment: 4 pages, 3 figures, Prepared for the 10th International Conference on
Astroparticle and Underground Physics (TAUP 2007), Sendai, Japan, 11-15 Sep
200
Electrically injected cavity polaritons
We have realised a semiconductor quantum structure that produces
electroluminescence while operating in the light-matter strong coupling regime.
The mid-infrared light emitting device is composed of a quantum cascade
structure embedded in a planar microcavity, based on the GaAs/AlGaAs material
system. At zero bias, the structure is characterised using reflectivity
measurements which show, up to room temperature, a wide polariton anticrossing
between an intersubband transition and the resonant cavity photon mode. Under
electrical injection the spectral features of the emitted light change
drastically, as electrons are resonantly injected in a reduced part of the
polariton branches. Our experiment demonstrates that electrons can be
selectively injected into polariton states up to room temperature.Comment: 10 pages, 4 figure
Strong enhancement of extremely energetic proton production in central heavy ion collisions at intermediate energy
The energetic proton emission has been investigated as a function of the
reaction centrality for the system 58Ni + 58Ni at 30A MeV. Extremely energetic
protons (EpNN > 130 MeV) were measured and their multiplicity is found to
increase almost quadratically with the number of participant nucleons thus
indicating the onset of a mechanism beyond one and two-body dynamics.Comment: 5 pages, 2 figures, submitted to Physical Review Letter
Contemporary presence of dynamical and statistical production of intermediate mass fragments in midperipheral Ni+Ni collisions at 30 MeV/nucleon
The reaction at 30 MeV/nucleon has been experimentally
investigated at the Superconducting Cyclotron of the INFN Laboratori Nazionali
del Sud. In midperipheral collisions the production of massive fragments
(4Z12), consistent with the statistical fragmentation of the
projectile-like residue and the dynamical formation of a neck, joining
projectile-like and target-like residues, has been observed. The fragments
coming from these different processes differ both in charge distribution and
isotopic composition. In particular it is shown that these mechanisms leading
to fragment production act contemporarily inside the same event.Comment: 9 pages, minor correction
Blastic plasmacytoid dendritic cell neoplasm: Genomics mark epigenetic dysregulation as a primary therapeutic target
Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and aggressive hematologic malignancy for which there is still no effective B therapy. In order to identify genetic alterations useful for a new treatment design, we used whole-exome sequencing to analyze 14 BPDCN patients and the patient-derived CAL-1 cell line. The functional enrichment analysis of mutational data reported the epigenetic regulatory program to be the most significantly undermined (P<0.0001). In particular, twenty-five epigenetic modifiers were found mutated (e.g. ASXL1, TET2, SUZ12, ARID1A, PHF2, CHD8); ASXL1 was the most frequently affected (28.6% of cases). To evaluate the impact of the identified epigenetic mutations at the gene-expression and Histone H3 lysine 27 trimethylation/acetylation levels, we performed additional RNA and pathology tissue-chromatin immunoprecipitation sequencing experiments. The patients displayed enrichment in gene signatures regulated by methylation and modifiable by decitabine administration, shared common H3K27-acetylated regions, and had a set of cell-cycle genes aberrantly up-regulated and marked by promoter acetylation. Collectively, the integration of sequencing data showed the potential of a therapy based on epigenetic agents. Through the adoption of a preclinical BPDCN mouse model, established by CAL-1 cell line xenografting, we demonstrated the efficacy of the combination of the epigenetic drugs 5’-azacytidine and decitabine in controlling disease progression in vivo
Neuromonitoring intraoperatorio del nervo laringeo ricorrente. Un’esperienza di 1000 pazienti consecutivi
Il neuromonitoring intraoperatorio è stato introdotto in chirurgia tiroidea molti anni fa rendendo più semplice l’identificazione del nervo laringeo ricorrente e meno frequenti i danni a suo carico. Tra il
1999 e il 2005 abbiamo raccolto tutti i dati relativi ai pazienti che si sono sottoposti a chirurgia tiroidea e li abbiamo analizzati anno per anno.
L’identificazione intraoperatoria del nervo è avvenuta nel 99,2% dei casi (1768 nervi a rischio). La percentuale di emitiroidectomie e tiroidectomie totali è passata dal 17% all’84%. Una minima disfunzione delle corde vocali dovuta a edema o ematoma è stata diagnosticata laringoscopicamente nel 2,9% dei casi. Le paresi permanenti(0,8% nel primo anno di studio) sono progressivamente diminuite fino ad attestarsi allo 0,32% complessivamente.
L’introduzione di questa metodica in chirurgia tiroidea è associata a una minore percentuale di paresi del nervo ricorrente anche se la frequenza dei disturbi motori di grado minore non è complessivamente mutata
A face for all seasons:searching for context-specific leadership traits and discovering a general preference for perceived health
Previous research indicates that followers tend to contingently match particular leader qualities to evolutionarily consistent situations requiring collective action (i.e., context-specific cognitive leadership prototypes) and information processing undergoes categorization which ranks certain qualities as first-order context-general and others as second-order context-specific. To further investigate this contingent categorization phenomenon we examined the “attractiveness halo”—a first-order facial cue which significantly biases leadership preferences. While controlling for facial attractiveness, we independently manipulated the underlying facial cues of health and intelligence and then primed participants with four distinct organizational dynamics requiring leadership (i.e., competition vs. cooperation between groups and exploratory change vs. stable exploitation). It was expected that the differing requirements of the four dynamics would contingently select for relatively healthier- or intelligent-looking leaders. We found perceived facial intelligence to be a second-order context-specific trait—for instance, in times requiring a leader to address between-group cooperation—whereas perceived health is significantly preferred across all contexts (i.e., a first-order trait). The results also indicate that facial health positively affects perceived masculinity while facial intelligence negatively affects perceived masculinity, which may partially explain leader choice in some of the environmental contexts. The limitations and a number of implications regarding leadership biases are discussed
NEMO: A Project for a km Underwater Detector for Astrophysical Neutrinos in the Mediterranean Sea
The status of the project is described: the activity on long term
characterization of water optical and oceanographic parameters at the Capo
Passero site candidate for the Mediterranean km neutrino telescope; the
feasibility study; the physics performances and underwater technology for the
km; the activity on NEMO Phase 1, a technological demonstrator that has
been deployed at 2000 m depth 25 km offshore Catania; the realization of an
underwater infrastructure at 3500 m depth at the candidate site (NEMO Phase 2).Comment: Proceeding of ISCRA 2006, Erice 20-27 June 200
Measurement of the atmospheric muon flux with the NEMO Phase-1 detector
The NEMO Collaboration installed and operated an underwater detector
including prototypes of the critical elements of a possible underwater km3
neutrino telescope: a four-floor tower (called Mini-Tower) and a Junction Box.
The detector was developed to test some of the main systems of the km3
detector, including the data transmission, the power distribution, the timing
calibration and the acoustic positioning systems as well as to verify the
capabilities of a single tridimensional detection structure to reconstruct muon
tracks. We present results of the analysis of the data collected with the NEMO
Mini-Tower. The position of photomultiplier tubes (PMTs) is determined through
the acoustic position system. Signals detected with PMTs are used to
reconstruct the tracks of atmospheric muons. The angular distribution of
atmospheric muons was measured and results compared with Monte Carlo
simulations.Comment: Astrop. Phys., accepte
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